Abstract:
Compositions and methods are provided for preparing nanosized biologically active agents, including agents formulated for target specific drug delivery. The nanosized agents are prepared with supercritical carbon dioxide as an antisolvent, providing nanoparticles whose size, shape, and surroundings are well-controlled. The nanoparticles are made of small molecules, e.g. drugs, anti-oxidants, luciferin, polypeptides, e.g. oligopeptides; polynucleotides, e.g. siRNA, antisense oligonucleotides, etc. In some embodiments, the nanoparticles comprise a polymer coating, which can provide for controlled delivery, targeting, controlled release, and the like. In other embodiments, the nanoparticles comprise a target specific tag for targeting the nanoparticles to a site of interest, e.g. tissue, cell, etc.
Abstract:
A beam modulation device gate is constructed from a silicon material, such as a silicon layer on an silicon on insulator wafer. The device further comprises a set of electrical contacts on the layer. The layer defines a set of electrically conducting silicon material fingers forming an array, wherein each of at least some of the fingers is connected electrically to one of the electrical contacts. The gate may be used in a mass or ion mobility spectrometer. Where the gate is constructed from a silicon on insulator wafer, an insulator layer supports the silicon layer and a handle layer supports the insulator layer. When predetermined electrical potentials are applied to the electrical contacts, at least some of the fingers will be substantially at said predetermined electrical potentials to modulate a beam of charged particles that passes through said array of fingers. A plurality of devices of the type above may be used, where each of the devices modulates the beam so that the beam is deflected along a direction different from direction along which the beam is deflected by any of the remaining devices. A plurality of devices of the type above may be used for a mass gate or charged particle buncher device. For making an ion optical device, an array of fingers is formed in a silicon layer of the silicon on insulator wafer. A portion of a handle layer of the wafer on a side of an insulator layer of the wafer opposite to that of the fingers is removed; and a portion of the insulator layer is removed so that the fingers are connected to the wafer only through the silicon layer and at one end of the fingers.
Abstract:
A method that comprises providing a polymerized sol-gel material (PSG) and linking an enzyme to a surface of the PSG via covalent linkage is provided. The surface of the PSG is derivatized with a linker that comprises a functional group for linking itself to the surface of the PSG and a functional group for linking itself with the enzyme. The linked-enzyme PSG, or microreactor, is an effective means of at least partially digesting a substrate, such as a biological substrate. The activity of the enzyme of the microreactor may be significantly enhanced, up to 200-fold for example, relative to the activity of the enzyme free of the microreactor. The microreactor is thus an effective vehicle for digesting a substrate such as a biomolecule, a protein, an oligonucleotide, a peptide, a steroid, and/or an organic acid, after which, any remaining substrate and one or more digestion product(s) may be separated and detected. Microreactors and integrated devices that incorporate microreactors, such as columns, pipet tips, wells, and well-plates, are also provided.
Abstract:
A more energy-efficient method of processing crude oil is achieved by viscoelastic shearing in order to increase the vapor pressure of the crude oil. This change in vapor pressure allows a more efficient separation of volatile components from non-volatile components in the crude oil. By optimizing the energy expenditure for shearing and the energy expenditure for separating the volatile components from the non-volatile components of the crude oil, while simultaneously removing the volatile components by distillation, one can reduce the overall energy input for the separation. Alternatively, it is possible to affect the distillation at a reduced temperature.
Abstract:
A beam modulation device gate is constructed from a silicon material, such as a silicon layer on an silicon on insulator wafer. The device further comprises a set of electrical contacts on the layer. The layer defines a set of electrically conducting silicon material fingers forming an array, wherein each of at least some of the fingers is connected electrically to one of the electrical contacts. The gate may be used in a mass or ion mobility spectrometer. Where the gate is constructed from a silicon on insulator wafer, an insulator layer supports the silicon layer and a handle layer supports the insulator layer. When predetermined electrical potentials are applied to the electrical contacts, at least some of the fingers will be substantially at said predetermined electrical potentials to modulate a beam of charged particles that passes through said array of fingers. A plurality of devices of the type above may be used, where each of the devices modulates the beam so that the beam is deflected along a direction different from direction along which the beam is deflected by any of the remaining devices. A plurality of devices of the type above may be used for a mass gate or charged particle buncher device. For making an ion optical device, an array of fingers is formed in a silicon layer of the silicon on insulator wafer. A portion of a handle layer of the wafer on a side of an insulator layer of the wafer opposite to that of the fingers is removed; and a portion of the insulator layer is removed so that the fingers are connected to the wafer only through the silicon layer and at one end of the fingers.
Abstract:
By connecting the Bradbury-Nielson gate (BNG) directly to a driver without a transmission line, distortion of the voltage waveform experienced a the BNG are much reduced. Because the magnitude of the modulation defects grows as the applied modulation voltage is increased, Bradbury-Nielson gates with finer wire spacing such as 100 microns, and operating at 10 to 15 V, significantly better signal-to-noise ratios are achieved. HT-TOFMS data were also post processed using an exact knowledge of the modulation defects.
Abstract:
Improved crude oil processing is achieved by viscoelastic shearing of crude oil at an elevated temperature. The shearing provides for an enriched light fraction and an enriched heavy fraction that can be more efficiently separated by distillation. Shearing is achieved using a mobile surface and immobile surface, or other flow geometry, under conditions providing for a transient phase separation.
Abstract:
A method that comprises providing a polymerized sol-gel material (PSG) and linking an enzyme to a surface of the PSG via covalent linkage is provided. The surface of the PSG is derivatized with a linker that comprises a functional group for linking itself to the surface of the PSG and a functional group for linking itself with then enzyme. The linked-enzyme PSG, or microreactor, is an effective means of at least partially digesting a substrate, such as a biological substrate. The activity of the enzyme of the microreactor may be significantly enhanced, up to 200-fold for example, relative to the activity of the enzyme free of the microreactor. The microreactor is thus an effective vehicle for digesting a substrate such as a biomolecule, a protein, an oligonucleotide, a peptide, a steroid, and/or an organic acid, after which, any remaining substrate and one or more digestion product(s) may be separated and detected. Microreactors and integrated devices that incorporate microreactors, such as columns, pipet tips, wells, and well-plates, are also provided.
Abstract:
A rapid and sensitive detection method capable of reliably distinguishing fragments identical to a defined sequence from fragments containing a single base pair mismatch relative to the defined sequence. The method employs a peptide analog antisense probe, such as a peptide nucleic acid (PNA) probe, which hybridizes with DNA to forms complexes having higher thermal stability, but greater sensitivity to base pair mismatches, than corresponding DNA/DNA complexes. The method may be used in a number of applications, including genetic screening and hybridization sequencing applications.